Device for locking joints



(No Model-.

' E'. L. GAYLORD.

DEVICE FOR LOOKING JOINTS. i No, 313,193. Patented Mar. 3, 1885.

ZU ifnesses E 6261/67/72 L. qyZoraZ w. avw zwr 29 UNrrED STATES EDWARD LFGAYLORD, OF BRIDGEPOR'I, CONNECTICUT.

v DEVICE FOR LOOKING JOINTS.

SPECIFICATION forming part of Letters Patent No. 313,193, dated March 3, 1885.

' Application filed September 3, 1884. (No model.)

To a whom, it may concern:

Be it known that I, EDWARD L. GAYLORD, a citizen of the United States, residing at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Devices for Looking Joints; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to certain novel and useful improvements in devices for securing joints, and has for its object to provide such I 5 a device by means of which the two portions of wood forming the joint may be securely held together without brads, nails, or ordinary screws, which mar the exterior of the joint; and with these ends in view my invention 2o consists in the details of construction and combination of elements hereinafter fully and in detail explained, and then specifically designated by the claims.

In order that those skilled in the art to which my invention appertains may more fully understand its construction and operation, I will proceed to describe the same in detail, referring by letter to the accompanying drawings, forming a part of this specifica- 0 tion, in which-- Figure l is a plan View of a joint secured by means of my improvement, and having the wood broken away to show its operation; Fig. 2, an elevation of my device, and Fig. 3 an 5 end view of the same in position.

Similar letters denote like parts in the several figures of the drawings.

A are the portions of wood to be joined together, and provided in theirmeeting surfaces 0 with recesses B, conformed to the shape of the locking device in cross-section, corresponding to one another in position, and entering the wood at right angles to the surfaces to be j oined. The edges of the meeting surfaces are, at C, so

5 cut away at right angles to the recesses just described as to leave space for the tightening of thejoint, as will be presently explained.

D is a right-and-left-hand mutilated screw, provided atits center with a square portion,

E, upon which a wrench may hold. This screw is cast with threads only on the opposite sides of the body, so that said screw presents an oval appearance. I

F are ordinary dowels fitting into corresponding recesses, G, for the purpose of pre 5 5 venting any twisting of the joint.

The operation of my improvement is as fol lows: The meeting surfaces to be joined having been matched, the recesses for the reception of the locking device formed, and the meeting edges cut away, as at C, Fig. 1, the ends of the screw are inserted within the re cesses B and the meeting surfaces of the joint placed in position. Then by means of a wrench applied at E a quarter or threeeighths turn is given to the screw, the sharp edges of the threads are embedded in the wood at the sides of the recesses and form for themselves a female thread, thus both drawing and holding the two pieces of woodform- 7o ing the joint firmly together.

When desired, the dowels or other auxiliary means of security may be done away with and two of the mutilated screws used, thus preventing any wringing of the joint.

I do not wish to be confined to the exact shape or design of screw used, as the gist of my invention rests in the broad idea of the use, in the connection hereinbefore set forth, of a double-ended mutilated screw.

Having thus described my invention,what I claim as new, and desire to secure by Letters Patent, is

1. In combinationwith the two portions of a joint, a right-and-left-hand mutilated screw, 8 5 constructed and adapted as hereinbefore set forth,

2. The combination, with a mutilated screw, as described, provided at its central portion with a wrench-hold, of the two portions of 0 wood forming a joint, having recesses therein corresponding to one another, at right angles to the surfaces to be j oined, conformed in cross section to the shape of the locking device, and adapted to receive the respective ends of the 5 screw, substantially as set forth.

3. The combination, with the screw as described, of the two portions of wood provided with recesses, as described, and having their meeting edges cut away at right angles to roe said recesses, whereby the wrench-hold upon ofi thereby drawing and holding said surfaces the screw may be readily reached, substantightly together, substantial1y ashereinbefore tially as described. shown and specified.

4. In a device for securing the meeting sur- In testimony whereof I affix my signature in 5 faces of a joint, the joint having the said snrpresence of two witnesses.

faces cut away and recessed, as described, in EDWARD L GAYLORD combination with the double-ended screw 1 having right and left threads, mutilated, as \Vitnesses:

described, and adapted to be inserted within S. S. WILLIAMSON, 10 said recesses and cam against the walls there- WV. T. HAVILAND. 

